R33 Gtst Overheating

[caliibre]

just bought a skyline r33 gtst a few days ago

want to know why its overheating

it started overheating today because the previous guy put techaloy 60 in, i filled it up with 90, the reservoir was at full mark, and when it overheated it went about 3-4cm above the full mark and the radiator had barely any coolant in it, n the coolant in the reservoir was boiling for about 10-15 mins...

so i did a coolant flush, put techaloy performance 100 in

but after about 30-45min drive it started overheating, the coolant in the reservoir was almost empty (was up to the full line before) but the radiator still had the right amount of coolant in it...

i cant figure out the problem, the cap seems alright, the thermo was opening because it was able to bleed the coolant

p.s. when it overheats it only ever got to the white line iust before it hit the hot mark (the white line is bout 5mm before the hot line), so it never hit hot

anyone got any ideas? much appreciated

Edited January 19, 2011 by caliibre

[Joe_89]

just bought a skyline r33 gtst a few days ago

want to know why its overheating

it started overheating today because the previous guy put techaloy 60 in, i filled it up with 90, the reservoir was at full mark, and when it overheated it went about 3-4cm above the full mark and the radiator had barely any coolant in it, n the coolant in the reservoir was boiling for about 10-15 mins...

so i did a coolant flush, put techaloy performance 100 in

but after about 30-45min drive it started overheating, the coolant in the reservoir was almost empty (was up to the full line before) but the radiator still had the right amount of coolant in it...

i cant figure out the problem, the cap seems alright, the thermo was opening because it was able to bleed the coolant

p.s. when it overheats it only ever got to the white line iust before it hit the hot mark (the white line is bout 5mm before the hot line), so it never hit hot

anyone got any ideas? much appreciated

Im guessing you have checked for leaks?

Doesnt need a very big leak to start overheating, and if your loosing coolant to then that seems like the obvious cause

[caliibre]

yeah checked for leaks but couldnt find any, it most likely came from the reservoir the first time

but the second time i have no idea...

[SECURITY]

thing about the factory water temp gauge is as soon as it moves above where the operating temperature (which is just under half way) it means your water temp has hit 105 degrees. if its hit that a few times you've probably blown your head gasket.

a few ways to check if you've done this is to check for the following;

- milky substance in your radiator or oil cap (if its cracked through an oil galley)

- constant bubbles in your coolant (if its cracked through your combustion chamber)

- white smoke out of your exhaust (water going through your combustion chamber)

are you getting any of these?

[SECURITY]

double post

Edited January 19, 2011 by SECURITY

[MBS206]

Throw a new radiator cap on it.

[caliibre]

yeah i thought i might have blown my head gasket but

-dont have any milky substance in radiator or oil cap (though when i pumped the old coolant out of the reservoir towards the end it looked clear almost like water, kinda milky)

-dont see anything wrong with the bubbling side of coolant

-not sure about white smoke coming from exhaust

new radiator cap ay?

[89CAL]

Did you bleed the air from the system both times you replaced the coolant?

[BIG MACCA]

thing about the factory water temp gauge is as soon as it moves above where the operating temperature (which is just under half way) it means your water temp has hit 105 degrees. if its hit that a few times you've probably blown your head gasket.

a few ways to check if you've done this is to check for the following;

- milky substance in your radiator or oil cap (if its cracked through an oil galley)

- constant bubbles in your coolant (if its cracked through your combustion chamber)

- white smoke out of your exhaust (water going through your combustion chamber)

are you getting any of these?

The first tip happened to my R33 GTR just last week and i have done the gasket maybe a cracked head. Mine has oil getting into the coolant . I noticed mine getting when it was to late blew a big hole in radiator hose. Hope yours hasn't done the same thing i am up for big $$$ to fix it.

[mad082]

possibly try a new cap and see if that makes a difference (make sure you get the same pressure cap).

possible causes of overheating are:

dodgy cap

dodgy thermostat

leak in the system (including blown head gasket)

dodgy water pump

blocked radiator (which a flush will do nothing to help)

shagged clutch fan (although driving at highway speed it won't overheat)

[t_revz]

had mine up to 119 on powerfc readout twice after the water pump leaked out the telltale hole and it was only half full. got it to a mates both times and fed water into it real slow. did another 50000km before rebuild due to damaged rings but head was ok. maybe i was just lucky but mine was well into the red so yours may be fine too

[BIG MACCA]

Here is a picture of my radiator cap

[Tony de Wonderful]

Here is a picture of my radiator cap

Oh dear.

[mad082]

Oh dear.

+1

[caliibre]

got a new cap, wasnt the fix

bought a new radiator and viscus, that seemed to fix the problem, not overheating so all good

but now theres white smoke coming outta the radiator when its reving, probably head gaskets gone

[SECURITY]

get it pressure tested to find out for sure.